1. Field of the Invention
The present invention relates to a golf club head. In particular, the present invention relates to a golf club head whose center of gravity can be adjusted.
2. Description of Related Art
FIG. 1 is a perspective view of a conventional golf club head. FIG. 2 is a sectional view of the golf club head in FIG. 1. FIG. 2a is an enlarged view of a circled portion in FIG. 2. The golf club head 1 is made of metal and includes a golf club head body 10, a striking plate 11, a perimeter wall 12, a hosel 13, and a vibration-absorbing plate 14. The striking plate 11 is mounted to a front side of the golf club head body 10 for striking a golf ball. The perimeter wall 12 is a wall that extends rearward along a perimeter of the golf club head body 10 and forms an opening 121 in a back of the golf club head body 10. A shaft (not shown) is engaged with the hosel 13. The vibration-absorbing plate 14 is made of rubber or carbon fiber and bonded by glue to a back of the striking plate 11 for absorbing vibrations generated as a result of striking a golf ball.
The upper part of the perimeter wall 12 and the hosel 13 have a considerable weight such that the center of gravity 15 of the golf club head 1 is in a relatively high position. This may result in a reduction in the inertial moment of the golf club head 1 and a decrease in the momentum-transferring efficiency from the striking plate to the golf ball as well as vibrations of the golf club head 1 while striking a golf ball. The striking effect and striking stability of the golf club head 1 are greatly and adversely affected.
As illustrated in FIG. 2a, if the striking plate 11 is mounted to an engaging portion 101 of the golf club head body 10 by welding, brazing, insertion, or pressing, an engaging edge 111 (such as a welding bead, an outflow of the material for brazing, an insertion area, or a pressing area) is formed in a joint area between the striking plate 11 and the golf club head body 10. When striking a golf ball, the resultant vibrations may cause a stress concentration around the engaging edge 111. The result of long-term stress concentration in the engaging edge 111 is cracks in the engaging edge 111, adversely affecting the structural strength of the golf club head 1. Although a vibration-absorbing plate 14 is bonded to the golf club head body 10, the bonding arrangement results in a gap 142 between the vibration-absorbing plate 14 and the golf club head body 10. The vibration-absorbing plate 14 could not absorb the concentrated stress due to existence of the gap 142; namely, the vibration-absorbing efficiency of the vibration-absorbing plate 14 is adversely affected by the gap 142.